The present invention relates to a control system for use in an automobile, in public systems (such as a water supply system, a sewerage system and a traffic system), in a power supply system, and in a nuclear power plant, and more particularly to an analogical inference apparatus for control of a system suitable for use in a case where a detected control condition is fuzzy and is different from predetermined control conditions.
The system control based upon fuzzy control rules has been discussed in an article entitled "Speed Control of Automobile by Fuzzy Logic Controller" by Maeda et al. (Proceeding of 9th system symposium, Aug., 1983, pages 7 to 10). The article describes a simple system control which is achieved by six control rules including a control rule that says "if the control deviation is positive, make the change of the quantity of operation positive". This control method, however, pays no attention to a case where a control condition corresponding to the condition that "if the control deviation is positive", is absent.